Electronic modules, such as electronic or optoelectronic transceiver or transponder modules, are increasingly used in electronic and optoelectronic communication. Some modules can be plugged into a variety of host networking equipment. Multi-Source Agreements (“MSAs”), such as the X2 MSA and 10 Gb/s Small Form Factor Pluggable (“XFP”) MSA specify, among other things, package dimensions for modules. Conformity with an MSA allows a module to be plugged into host equipment designed in compliance with the MSA. Modules typically communicate with a printed circuit board of a host device by transmitting electrical signals to the printed circuit board and receiving electrical signals from the printed circuit board. These electrical signals can then be transmitted by the module outside the host device as optical and/or electrical signals.
One common difficulty associated with modules is the generation of electromagnetic radiation that can result in electromagnetic interference (“EMI”) in surrounding devices. The generation of electromagnetic radiation by a module is a matter of significant concern because any resulting EMI can seriously impair, if not prevent, the proper operation of other systems and devices in the vicinity. Thus, the containment of electromagnetic radiation is an important consideration in the design and use of electronic and optoelectronic transceiver and transponder modules.
There are a number of parameters that bear on the generation of electromagnetic radiation and the containment of electromagnetic radiation in modules. For example, the generation of electromagnetic radiation is a function, at least in part, of the data rate of the module. Thus, for example, the level of electromagnetic radiation associated with the operation of a 2 Gb/s module may not be of particular concern, while the level of electromagnetic radiation associated with the operation of a 10 Gb/s module can present significant problems in some cases. As data rates increase, the reliable containment of electromagnetic radiation has become increasingly important.
In recognition of the problems presented by electromagnetic radiation, various attempts have been made to contain electromagnetic radiation. Many of such attempts have focused on the development of various types of structures intended to contain, to the extent practicable, the electromagnetic radiation that causes EMI. However, the problems and deficiencies inherent in such attempts have become increasingly evident as data rates and corresponding operational frequencies increase. Thus, the problems associated with typical electromagnetic radiation containment structures appear likely to get worse with the passage of time unless adequate solutions are developed and implemented.
Another challenge inherent in modules concerns the generation of heat during the operation of the modules. This heat, if not dissipated, can cause a module to malfunction or to become damaged. A heat sink that is external to and separate from a module is sometimes used in connection with the module to help dissipate the heat generated by the module. However, such arrangements are only effective where there is substantial contact between the heat sink and one or more surfaces of the module. Such contact may not be readily attained where discontinuities and other imperfections exist in the heat sink and/or the module surfaces.